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Alireza Shoae-Hassani Peyman Keyhanvar Alexander Marcus Seifalian Seyed Abdolreza Mortazavi-Tabatabaei Narmin Ghaderi Khosro Issazadeh Nour Amirmozafari Javad Verdi 《PloS one》2013,8(11)
Using phages is a novel field of cancer therapy and phage nanobioparticles (NBPs) such as λ phage could be modified to deliver and express genetic cassettes into eukaryotic cells safely in contrast with animal viruses. Apoptin, a protein from chicken anemia virus (CAV) has the ability to specifically induce apoptosis only in carcinoma cells. We presented a safe method of breast tumor therapy via the apoptin expressing λ NBPs. Here, we constructed a λ ZAP-CMV-apoptin recombinant NBP and investigated the effectiveness of its apoptotic activity on BT-474, MDA-MB-361, SKBR-3, UACC-812 and ZR-75 cell lines that over-expressing her-2 marker. Apoptosis was evaluated via annexin-V fluorescent iso-thiocyanate/propidium iodide staining, flow-cytometric method and TUNEL assay. Transfection with NBPs carrying λ ZAP-CMV-apoptin significantly inhibited growth of all the breast carcinoma cell lines in vitro. Also nude mice model implanted BT-474 human breast tumor was successfully responded to the systemic and local injection of untargeted recombinant λ NBPs. The results presented here reveal important features of recombinant λ nanobioparticles to serve as safe delivery and expression platform for human cancer therapy. 相似文献
2.
Finlay A. McAlister Erik Youngson Jeffrey A. Bakal Jayna Holroyd-Leduc Narmin Kassam 《CMAJ》2015,187(14):1041-1048
Background:
Physician scores on examinations decline with time after graduation. However, whether this translates into declining quality of care is unknown. Our objective was to determine how physician experience is associated with negative outcomes for patients admitted to hospital.Methods:
We conducted a retrospective cohort study involving all patients admitted to general internal medicine wards over a 2-year period at all 7 teaching hospitals in Alberta, Canada. We used files from the Alberta College of Physicians and Surgeons to determine the number of years since medical school graduation for each patient’s most responsible physician. Our primary outcome was the composite of in-hospital death, or readmission or death within 30 days postdischarge.Results:
We identified 10 046 patients who were cared for by 149 physicians. Patient characteristics were similar across physician experience strata, as were primary outcome rates (17.4% for patients whose care was managed by physicians in the highest quartile of experience, compared with 18.8% in those receiving care from the least experienced physicians; adjusted odds ratio [OR] 0.88, 95% confidence interval [CI] 0.72–1.06). Outcomes were similar between experience quartiles when further stratified by physician volume, most responsible diagnosis or complexity of the patient’s condition. Although we found substantial variability in length of stay between individual physicians, there were no significant differences between physician experience quartiles (mean adjusted for patient covariates and accounting for intraphysician clustering: 7.90 [95% CI 7.39–8.42] d for most experienced quartile; 7.63 [95% CI 7.13–8.14] d for least experienced quartile).Interpretation:
For patients admitted to general internal medicine teaching wards, we saw no negative association between physician experience and outcomes commonly used as proxies for quality of inpatient care.Many jurisdictions have instituted compulsory recertification of physicians on the assumption that quality of care declines with experience. Although a systematic review reported that 32 of 62 studies found decreasing performance with increasing physician experience, most of these studies evaluated performance on examinations or hypothetical vignettes rather than actual quality of care provided to patients, and most of the studies were done decades ago, before the widespread availability of tools to readily facilitate evidence-based medicine.1Experience is strongly related to better outcomes in surgery and obstetrics, but studies examining the association between physician experience and quality of care for medical patients have reported mixed results.1–8 Many of the studies reporting an inverse association between experience and quality of care have focused on the provision of “guideline recommended tests or therapies” as a proxy for quality of care. However, guideline recommendations might not be appropriate in every situation.An evaluation of broader quality metrics may be more appropriate to answer this question. For example, in-hospital mortality and readmission rates or mortality postdischarge are commonly used as markers for quality of inpatient care, are endorsed by the Centers for Medicare & Medicaid Services and are included in the Patient Protection and Affordable Care Act.9,10 However, to our knowledge, few studies have examined the association between these broader quality metrics and physician experience, and these studies have been limited. They either focused on single diagnoses,11 excluded older adult patients,2 examined data from only 1 hospital8 or combined data7 for both surgeons and physicians.Patients admitted to general internal medicine services at Alberta teaching hospitals are distributed between wards purely on the basis of bed availability, and attending physicians rotate every 1–4 weeks. For these reasons, the distribution of patients between attending physicians is quasirandom. We took advantage of this natural experiment to evaluate the association between attending physician experience (years since medical school graduation) and outcomes for patients admitted to general internal medicine wards in Alberta. 相似文献3.
Zehsaz Farzad Safabakhsh Amir Hamzeh Farhangi Negin Keynezhad Narmin Monfaredan Amir Ghahramani Mehri 《Molecular biology reports》2019,46(2):1835-1843
Molecular Biology Reports - We studied to ascertain whether the ACE and/or CKMM genotypes independently influence the baseline level of some sport performances in 613 inactive male adolescents... 相似文献
4.
Narmin Ghaffari Laleh Chiara Maria Lavinia Loeffler Julia Grajek Kateina Stakov Alexander T. Pearson Hannah Sophie Muti Christian Trautwein Heiko Enderling Jan Poleszczuk Jakob Nikolas Kather 《PLoS computational biology》2022,18(2)
Classical mathematical models of tumor growth have shaped our understanding of cancer and have broad practical implications for treatment scheduling and dosage. However, even the simplest textbook models have been barely validated in real world-data of human patients. In this study, we fitted a range of differential equation models to tumor volume measurements of patients undergoing chemotherapy or cancer immunotherapy for solid tumors. We used a large dataset of 1472 patients with three or more measurements per target lesion, of which 652 patients had six or more data points. We show that the early treatment response shows only moderate correlation with the final treatment response, demonstrating the need for nuanced models. We then perform a head-to-head comparison of six classical models which are widely used in the field: the Exponential, Logistic, Classic Bertalanffy, General Bertalanffy, Classic Gompertz and General Gompertz model. Several models provide a good fit to tumor volume measurements, with the Gompertz model providing the best balance between goodness of fit and number of parameters. Similarly, when fitting to early treatment data, the general Bertalanffy and Gompertz models yield the lowest mean absolute error to forecasted data, indicating that these models could potentially be effective at predicting treatment outcome. In summary, we provide a quantitative benchmark for classical textbook models and state-of-the art models of human tumor growth. We publicly release an anonymized version of our original data, providing the first benchmark set of human tumor growth data for evaluation of mathematical models. 相似文献
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Adaptation of human embryonic stem cells to feeder-free and matrix-free culture conditions directly on plastic surfaces 总被引:2,自引:0,他引:2
Bigdeli N Andersson M Strehl R Emanuelsson K Kilmare E Hyllner J Lindahl A 《Journal of biotechnology》2008,133(1):146-153
Previous studies have shown that cultivation of undifferentiated human embryonic stem (hES) cells requires human fibroblasts (hF) or mouse embryonic fibroblast (mEF) feeders or a coating matrix such as laminin, fibronectin or Matrigel in combination with mEF or hF conditioned medium. We here demonstrate a successful feeder-free and matrix-free culture system in which undifferentiated hES cells can be cultured directly on plastic surfaces without any supportive coating, in a hF conditioned medium. The hES cells cultured directly on plastic surfaces grow as colonies with morphology very similar to cells cultured on Matrigel(TM). Two hES cell lines SA167 and AS034.1 were adapted to matrix-free growth (MFG) and have so far been cultured up to 43 passages and cryopreserved successfully. The lines maintained a normal karyotype and expressed the expected marker profile of undifferentiated hES cells for Oct-4, SSEA-3, SSEA-4, TRA-1-60, TRA-1-81 and SSEA-1. The hES cells formed teratomas in SCID mice and differentiated in vitro into derivates of all three germ layers. Thus, the MFG-adapted hES cells appear to retain pluripotency and to remain undifferentiated. The present culture system has a clear potential to be scaleable up to a manufacturing level and become the preferred culture system for various applications such as cell therapy and toxicity testing. 相似文献
6.
Parviz Parvizi Ali Bordbar Narmin Najafzadeh 《Memórias do Instituto Oswaldo Cruz》2013,108(4):414-420
Individual, naturally occurring Phlebotomus
mongolensis and Phlebotomus caucasicus from Iran
were screened for infections with the maternally inherited intracellular
Rickettsia-like bacterium Wolbachia
pipientis via targeting a major surface protein gene (wsp). The
main objective of this study was to determine if W. pipientis
could be detected in these species. The sandflies were screened using polymerase
chain reaction to amplify a fragment of the Wolbachia surface
protein gene. The obtained sequences were edited and aligned with database
sequences to identify W. pipientis haplotypes. Two strains of
Wolbachia were found. Strain Turk 54 (accession )
is widespread and has previously been reported in Phlebotomus
papatasi and other insects. Strain Turk 07 (accession EU780683) is
a novel strain, found for first time in the two sister species. A-group strains
of W. pipientis occur throughout much of the habitat of these
sandflies. It is possible that Wolbachia is transferred via
horizontal transmission. Horizontal transfer could shed light on sandfly control
because Wolbachia is believed to drive a deleterious gene into
sandflies that reduces their natural population density. With regard to our
findings in this study, we can conclude that one species of sandfly can be
infected with different Wolbachia strains and that different
species of sandflies can be infected with a common strain. KC576916相似文献
7.
Ian Kracalik Rakif Abdullayev Kliment Asadov Rita Ismayilova Mehriban Baghirova Narmin Ustun Mazahir Shikhiyev Aydin Talibzade Jason K. Blackburn 《PLoS neglected tropical diseases》2014,8(7)
We assessed spatial and temporal changes in the occurrence of human anthrax in Azerbaijan during 1984 through 2010. Data on livestock outbreaks, vaccination efforts, and human anthrax incidence during Soviet governance, post-Soviet governance, preemptive livestock vaccination were analyzed. To evaluate changes in the spatio-temporal distribution of anthrax, we used a combination of spatial analysis, cluster detection, and weighted least squares segmented regression. Results indicated an annual percent change in incidence of +11.95% from 1984 to 1995 followed by declining rate of −35.24% after the initiation of livestock vaccination in 1996. Our findings also revealed geographic variation in the spatial distribution of reporting; cases were primarily concentrated in the west early in the study period and shifted eastward as time progressed. Over twenty years after the dissolution of the Soviet Union, the distribution of human anthrax in Azerbaijan has undergone marked changes. Despite decreases in the incidence of human anthrax, continued control measures in livestock are needed to mitigate its occurrence. The shifting patterns of human anthrax highlight the need for an integrated “One Health” approach that takes into account the changing geographic distribution of the disease. 相似文献
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